'\" t
.\"     Title: uuidd
.\"    Author: [see the "AUTHOR(S)" section]
.\" Generator: Asciidoctor 2.0.15
.\"      Date: 2021-06-02
.\"    Manual: System Administration
.\"    Source: util-linux 2.37.2
.\"  Language: English
.\"
.TH "UUIDD" "8" "2021-06-02" "util\-linux 2.37.2" "System Administration"
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.SH "NAME"
uuidd \- UUID generation daemon
.SH "SYNOPSIS"
.sp
\fBuuidd\fP [options]
.SH "DESCRIPTION"
.sp
The \fBuuidd\fP daemon is used by the UUID library to generate universally unique identifiers (UUIDs), especially time\-based UUIDs, in a secure and guaranteed\-unique fashion, even in the face of large numbers of threads running on different CPUs trying to grab UUIDs.
.SH "OPTIONS"
.sp
\fB\-d\fP, \fB\-\-debug\fP
.RS 4
Run uuidd in debugging mode. This prevents uuidd from running as a daemon.
.RE
.sp
\fB\-F\fP, \fB\-\-no\-fork\fP
.RS 4
Do not daemonize using a double\-fork.
.RE
.sp
\fB\-k\fP, \fB\-\-kill\fP
.RS 4
If currently a uuidd daemon is running, kill it.
.RE
.sp
\fB\-n\fP, \fB\-\-uuids\fP \fInumber\fP
.RS 4
When issuing a test request to a running \fBuuidd\fP, request a bulk response of \fInumber\fP UUIDs.
.RE
.sp
\fB\-P\fP, \fB\-\-no\-pid\fP
.RS 4
Do not create a pid file.
.RE
.sp
\fB\-p\fP, \fB\-\-pid\fP \fIpath\fP
.RS 4
Specify the pathname where the pid file should be written. By default, the pid file is written to \fI{runstatedir}/uuidd/uuidd.pid\fP.
.RE
.sp
\fB\-q\fP, \fB\-\-quiet\fP
.RS 4
Suppress some failure messages.
.RE
.sp
\fB\-r\fP, \fB\-\-random\fP
.RS 4
Test uuidd by trying to connect to a running uuidd daemon and request it to return a random\-based UUID.
.RE
.sp
\fB\-S\fP, \fB\-\-socket\-activation\fP
.RS 4
Do not create a socket but instead expect it to be provided by the calling process. This implies \fB\-\-no\-fork\fP and \fB\-\-no\-pid\fP. This option is intended to be used only with \fBsystemd\fP(1). It needs to be enabled with a configure option.
.RE
.sp
\fB\-s\fP, \fB\-\-socket\fP \fIpath\fP
.RS 4
Make uuidd use this pathname for the unix\-domain socket. By default, the pathname used is \fI{runstatedir}/uuidd/request\fP. This option is primarily for debugging purposes, since the pathname is hard\-coded in the \fBlibuuid\fP library.
.RE
.sp
\fB\-T\fP, \fB\-\-timeout\fP \fInumber\fP
.RS 4
Make \fBuuidd\fP exit after \fInumber\fP seconds of inactivity.
.RE
.sp
\fB\-t\fP, \fB\-\-time\fP
.RS 4
Test \fBuuidd\fP by trying to connect to a running uuidd daemon and request it to return a time\-based UUID.
.RE
.sp
\fB\-V\fP, \fB\-\-version\fP
.RS 4
Output version information and exit.
.RE
.sp
\fB\-h\fP, \fB\-\-help\fP
.RS 4
Display help screen and exit.
.RE
.SH "EXAMPLE"
.sp
Start up a daemon, print 42 random keys, and then stop the daemon:
.sp
.if n .RS 4
.nf
.fam C
uuidd \-p /tmp/uuidd.pid \-s /tmp/uuidd.socket
uuidd \-d \-r \-n 42 \-s /tmp/uuidd.socket
uuidd \-d \-k \-s /tmp/uuidd.socket
.fam
.fi
.if n .RE
.SH "AUTHOR"
.sp
The \fBuuidd\fP daemon was written by \c
.MTO "tytso\(atmit.edu" "Theodore Ts\(cqo" "."
.SH "SEE ALSO"
.sp
\fBuuid\fP(3),
\fBuuidgen\fP(1)
.SH "REPORTING BUGS"
.sp
For bug reports, use the issue tracker at \c
.URL "https://github.com/karelzak/util\-linux/issues" "" "."
.SH "AVAILABILITY"
.sp
The \fBuuidd\fP command is part of the util\-linux package which can be downloaded from \c
.URL "https://www.kernel.org/pub/linux/utils/util\-linux/" "Linux Kernel Archive" "."